Self-furring plaster board



March 26, 1935. F. A. MANSKE SELF FURRING PLASTER BOARD 2 Sheets-$heet 1Filed March 15, 1933 A ga m xux 5'1 lNV ENTOR FEED/I-MFINSKE.

AT lORNEY 2 Sheets-Sheet 2 MHNSKE. ATTORNEZ;

ENTOR mv FRED H.

March 26, 1935. F. A. MANSKE SELF FURRING PLASTER BOARD Filed March 15,1933 Patented Mar. 26, 1935 UNITED STATES PATENT OFFICE 1,995,393SELF-FURRING PLASTER BOARD Fred A. Manske, Chicago, Ill., assignor toUnited States Gypsum Company, Chicago, 111., a corporation of IllinoisApplication March 15, 1933, Serial No. 660,805 Claims. (Cl. 72-124) Thisinvention relates to articles of manufac- Fig. 1 is a perspective viewof one end of my ture used in building constructions, and hasrefimproved plaster board, erence more particularly to self-furringplaster Fig. 2 is a fragmentary face elevation of a secboards to be usedas a base for a coating of plastion of a wall with parts broken away todisclose 6 ter. the construction,

In the erection of the plastered walls of a build- Fig. 3 is atransverse sectional view through the ing, it is standard practice touse flat plaster wall construction, boards as a base for the plastercoat. The plas- Fig. 4 is a vertical sectional view through a ter boardsare commonly nailed to wooden studs .wall adjacent a stud,

with their edges lying in abutting relation to form Fig. 5 is asectional elevation through two of 10 board joints. One of thedifficulties experienced my improved plaster .boards in nested relation,in this type of construction, is thatthe plasterer Figs. 6 and '7 areface views of modified forms has a tendency to apply too thin a layer ofplasof perforated plaster board,

ter over the faces of the flat boards. As a result Fig. 8 is atransverse sectional view through an of this economizing on plaster, thewall over the imperforate plaster board with projections, 15

board joints is weak, and cracks are apt to form Fig. 9 is a transversesectional view through a in the plaster due, for example, to stresses insupfurther modified form of plaster board,

porting framework and foundations. In the past, Fig. 10 is a fragmentaryplan view of a modified it has also been customary to depend on theadform of board with spot grounds, and

hesion between the plaster and the paper cover Figs. 11 and 12 arefragmentary sectional views 20 sheet to hold the layer of plaster inposition on through modified forms of plaster board.

the wall. However, under certain conditions, The improved plasterboardcomprises a core 12 such as in the case of fire, the plaster layer sepofcementitious material, such as a composition arates from the plasterboard and the wall fails composed largely of gypsum together with otherprematurely as a result. In the manufacture of ingredients such asvegetable fiber, foam, etc. A 25 the fiat plaster boards, the cost ofdrying is abrear paper cover sheet 13 is applied to one face of normallyhigh as the steam from the core mathe core 12 during the manufacture ofthe plaster terial cannot pass freely through the imperforate board, anda front .paper cover sheet 14 is applied cover sheets as the boardpasses through the dryto the other face of the core 12. The cover sheeti0 ing n- 14 is preferably folded about one edge of the core An objectof this invention therefore, is to pro- 12 and has a flap 15 which isadhesively attached Vide a Plaster board av p t grounds or furto theinner edge of cover sheet 13. While a prering D J'e 0n t front ac or thepurferred type of board has been described, the term D e o f rc g theplasterer to apply the p oper plaster board should be construedgenerically thickness o p as a thus e s the plObto include otherdesirable types of building board. abil ty f C ac g of h plaster. One ofthe salient features of the invention con- An th r o j t f th nv nt s tp vid a sists in forming the board at spaced points while plaster o rd hv n keying p n n ja n still in a plastic state, to provide rounded spotthe furrin pr j t n s ha h p ast lay grounds, nodes, projections orprotuberances 16 will be fi mly a d m an a y t d o he on the front faceof the board and mating roundplaster ed hollows 1'7 on the rear face ofthe board. The

Another obje of the mventlon 15 to provide a projections 16 on the faceof the board are joined plaster board which has a lower cost ofmanufact0 the plane fa e f the board by gentle curves tulje as a resultof decreased drymg tune less 18 so as not to interfere with the edge ofa trowel Welght per square foot as the plasterer applies a layer ofplaster 19 to the A further object of the invention is to provide a Se1ffurring plaster board in which the face of the board. In forming thenodes 16, the

forming dies are shaped to provide a radius of tuberances of oneboardwill nest into the protuberances of an adjoining b t p the hollowSomewhat less than the radius of ting shipment of the boards as bundledunits; the node 16 thus producing space 20 between also to improveplaster boards in other respect the hollows and nodes when the boardsare nested hereinafter specified and claimed, (Fig. 5). This arrangementpermits easier nest- Reference is to be had to the accompanying ing ofthe boards When y are sec red face to drawings forming a part of thisspecification, in face in bundles for shipment. The nodes are prefwhicherably arranged in staggered relation (Figs. 1 and Val 2) but they mayalso be spaced in rectangular relation (Figs. 6 and 7).

All or some of the nodes 16 are preferably provided with a keying hole21, so that when the plaster layer 19 is applied to the face of theboard, a portion of the plaster will pass through the hole and form abonding key 22 at the back of the board, thus materially increasing thefire resistance of the finished wall by preventing the plaster layerfrom breaking loose from the face of the board. The staggered relationof the nodes and hole is preferred as this staggered relation permitsgood bond of the plaster to the board, regardless of the position of astud 23 to which the boards are secured by nails 24. Only a few of theholes will lie over the stud with the staggered arrangement and evenwith these holes, the plaster has ample space to form the keys 22between the hollows 17 and the stud 23. After the scratch or base coatplaster 19 has been applied and dried, the second or browning coat ofplaster 25 and finishing coat plaster 26 are applied in the usual way toform the finished wall structure. If desired, the holes 21 may beomitted, thus producing a board as shown in Fig. 8 with projecting nodeson the front face of the board which will insure the application of areasonably thick coat of plaster. In the form of the invention shown inFig. 9, spot grounds or nodes 28 are provided on the front face of theboard, the hollows 1'7 being omitted leaving the back face of the boardflat. Each of the nodes 28 has a keying perforation 29 as previouslydescribed in connection with the other forms of the board. In themodified form of the board shown in Fig. 10, only about two spot groundsor nodes 30 are used on the face of the board. If the board size is 16inches by 48 inches, these two spot grounds preferably divide the boardinto three equal 16 inch spaces. A red or other colored marking line orindicator 31 may be provided across the rounded surface of each node 30to indicate the position of the stud to the workman who nails the boardsto the studs, the studs being commonly placed on 16 inch centers. Theindicator line 31 may also indicate to the workman where aboard may becut when breaking joints between boards, in order to secure the bestpossible arrangement.

In the modified form of board shown in Fig. 11, the back face of theboard 33 is provided with hollows 34 and a keying hole 35 passes throughthe board in each of said hollows 34. The front face 36 of the board iscoated with a layer of plaster 37 which passes through the hole 35 andforms a key 38 in the hollow 34. In this form of board, the hollow 34permits the plaster key 3'? to form, even if the hollow is locateddirectly over a stud.

The modified form of board shown in Fig. 12 has a smooth front surface39 and a rear surface 40 which has hollows 41. Holes 42 are formed inthe board in each of the hollows 41 by the use of a four corneredpointed punch so that the rear paper cover sheet forms outwardlyextending flaps 43 which partially protects and reinforces the core ofthe board inside the holes 42. The paper cover sheet on the front faceof the board forms fiaps 44 which curl outwardly to form spot grounds onthe front face of the board, thus insuring the application of asuificiently thick layer of plaster to the front face of the board.

In manufacturing an improved board, such as that shown in Figs. 1 and 2,a standard board machine is used in a manner well known to the art.

Such a machine delivers the plastic core material 12 between the coversheets 13 and 14. After the wet board has passed along the machine for aperiod sufficient to permit the core material to approach its settingpoint, the board is engaged by opposed chains of male and female dieswhich act on the two cover sheets to form the nodes 16 and hollows 1'7into the boards just before the setting of the board core 12. The diesthen disengage from the board and shortly after setting of the core 12,punches travel with the board a short distance and then return, to punchthe holes 21 through the board at the nodes desired to perforate.Instead of punching the holes in the boards while wet, the boards withthe formed nodes may be dried and bundled, the holes being drilledthrough the bundle of boards at the nodes by multiple spindle drills orthe like.

My improved plaster board presents many advantages over the standardtype of imperforate, flat boards and the following might be mentioned;

1. The board is self-furring thus insuring a proper thickness of plasterover the board and reducing cracking of the plaster.

2. The perforated board provides a strong mechanical key for theplaster, even when the perforations are positioned directly over thestud. thus insuring a high fire resistance in a wall and preventingseparation of the plaster from the board. A one hour fire rating can beobtained with my improved perforated board.

3. The perforations in the board cover sheets permit faster drying at alower cost due to the freer passage of moisture.

4. The improved board is easy studs and is easy to plaster over.

5. The board is lighter in weight thus reducing freight costs andproviding easier handling by the workman.

6. The boards nest readily for bundling preparatory to shipment.

'I. The board is strengthened by the reinforcing action of the nodesthus permitting the use of thinner cover sheets, a thinner core or both,with the same final strength of board.

8. The improved board provides better walls and ceilings in a building.

While I have described my invention as particularly applicable toplaster boards with cementitious cores and paper cover sheets, othertypes of panels or plaster boards, such as those made of fiber, may beused if desired.

I would state in conclusion that, while the illustrated examplesconstitute certain examples of the invention, I do not wish to limitmyself precisely to these details, since manifestly the same may beconsiderably varied without departing from the spirit of the inventionas defined in the appended claims.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- 1. An article of manufacture comprising a plasterboard having paper cover sheets and having projecting nodes on the frontface of said board and mating 'arcuate hollows on the rear face of saidboard, said board being provided with a hole through said board at aplurality of said nodes so as to permit plaster applied to said frontface to pass through said hole and form a key in a hollow withoutextending substantially beyond the rear face of said board.

2. An article of manufacture comprising a plaster board having acementitious core and paper cover sheets, said board having nodes protoapply to the jecting from the front surface of said board to providespot grounds to insure the application of a thick layer of plaster tosaid front face, said board having mating hollows on the rear facethereof to permit nesting during shipment one of said nodes having ahole passing through said board, the punched flaps of one of said coversheets being pressed inwardly and bonded to said core so as to reinforcesaid board around the periphery of said hole;

3. An article of manufacture comprising a plaster board having spacedrounded nodes on one face and mating rounded hollows on the otherface ofsaid board, the radii of said nodes and hollows being different toprovide nesting ability to said boards.

4. A building construction comprising a building frame, plaster boardssecured to said frame,

said boards having displaced hollows positioned over said frame andmating nodes projecting from the front face of said board, one or moreof said nodes being provided with a keying hole to permit plasterapplied to the front face of said board to pass through said hole andform a key in said hollow and in front of said frame.

5. A building construction comprising a building frame, plaster boardsecured to said frame, said board having displaced hollows at spacedintervals, at least certain of said hollows extending over said frame,and keying apertures passing completely through said board and throughat least some of said hollows, the apertured hol- 10Ws over said framepermitting substantial plaster keys to be formed at the back of theboard adjacent said frame.

FRED A. MANSKE.

